Chemical process for the treatment of the straw of flax or other plants.



UNITED STATES PATENT OFFICE. ANNE-MARIE DE MONTESSUS DE TAILORE, OFTUNIS, TUNIS, ASSIGNOR TO SOCIETE ANONYME POUR LA FABRICATION DES PATESA PAPIER DE LIN ET SUCGEDANES,

OF TUNIS, AFRICA.

CHEMICAL PROCESS FOR THE TREATMENT OF THE STRAW OF FLAX OR OTHER PLANTS.

Specification of Letters Patent.

Patented May 11, 1909.

Application filed April 17, 1906. Serial No. 312,276.

' exact description.

The present invention has for its object a chemical process for thetreatment of the straw of flax and other plants for the urpose ofseparating the utilizable fibers rom the wood. The separated fibers aretransformed into paper pulp, while the wood may be-collected andutilized for the manufacture of cardboard, common paper or for otherpurposes.

The process comprises a special chemical treatment succeeded bymethodical washing and it is this combination that constitutestheinvention, permitting of utilizing the straw of flax and other similarplants which is not used industrially, when they have been own for theproduction of grain and not 0 textile material.

The chemical treatment is based upon the fact that the fibers are apecto cellulose (C H O while the wood is constituted by the lignocellulose (0 K 0 and that these substances do not behave in the samemanner in the presence of bases and oxidants. V

The straw to be treated is first of all crushed and vigorously fannedupon gratings in order to free it from stones, dust and other impuritiesthat it contains. This preliminary crushing is not indispensable but itfacilitates the chemical treatment and permits of employing weakerbaths; further, crushed straw is more readily penetrated by -thechemical agents which act in a more uniform manner. This-cleaned strawis then subjected to a first treatment for the purpose of dissolving thecement which unites the fibers one with the other and causes the bundlesof fibers to adhere to the wood. This treatment may consist in rettingin the open or it may be based upon the action of'steam in the presenceof air 1; treatment with soda is also applicable. The

' mixture of non-adherent fibers and wood is then subjected to theaction of an oxidant in the presence of steam;this oxidant may be freechlorin or hypochlorite of lime, for example. This operation should beconducted in a suitable manner and stopped at the precise moment atwhich the wood is sufliciently oxidized, while the fiber has not yetundergone any transformation. Finally the material is raised to atemperature approximating 150 C. in thepresence of an alkaline bath, themost advantageous composition of which is as follows:

Caus tic soda (Na OH) 20 Carbonate of soda (Na CO H O) 50 Sulfate ofsoda (Na SO,) 20 Sulfite of sodium (NaSOQ 10 By appropriately conductingthese three operations, the order of which may be varied, the result isattained that the wood is completely resolved without attacking thefiber, so that methodical washing upon metallic gauzes of suitablenumber or coarseness, permits of eliminating all traces of wood and ofobtaining pure .fiber. This latter is then transformed into paper pulpby the ordinary processes of bleaching, breaking and so forth. The woodmay be collected, by decantation, in appropriately arranged tanks, forutilization in the manufacture of cardboard andpacking paper.

What I claim and desire to secure by Letters Patent of the United Statesis 1. The treatment of flax, straw and the described.

I 2. The treatment of flax, straw and the like for the purposespecified, which consists in eliminating therefrom the binding gumswhich unite the pecto and ligno cellulose structures, oxidizing theligno cellulose without injuriouslyafiecting the pecto cellu-' lose bysubjecting the cellulose mass to suitably oxidizing and alkalizingtreatment,

and recovering the ligno and pecto cellulose by decantation separatelyby passing the same through a strainer adapted to retain the pectocellulose fibers alone and subse- (Yilelltly recovering the lignocellulose from t e suspension water, substantially as described.

3. The treatment of flax, straw and the like for the purpose specified,which consists in eliminating therefrom the binding gums which unite theligno and pecto cellulose structures, subjecting the cellulose mass tothe action of'an oxidant in the presence of steam sufficiently tooxidize the lignowithout injuriously affecting the pecto cellulose,subjecting the mass to an alkali bath at a temperature of approximately150 C. and recovering the ligno and pecto cellulose by decantationseparately by passing the same through a strainer adapted to retain thepecto cellulose fibers alone and subsequently recovering the lignocellulose" from the suspension water, substantially as described.

In testimony whereof I have signed my name to this specification, in thepresence of two subscribing witnesses. v

ANNE-MARIE DE MONTESSUS DE BALLORE.

Witnesses:

RICHARD PRIANI, J. B.,DE MATTY.

